Pen cap



FIG. 1 is a front bottom side perspective view of the pen cap showing mynew design;

FIG. 2 is a front elevational view thereof,

FIG. 3 is a left elevational view thereof which is a mirror image of theright elevational view thereof;

FIG. 4 is a back elevational view thereof;

FIG. 5 is a bottom plan view thereof; and,

FIG. 6 is a top plan view thereof.

The broken lines depicting environmental structure are for illustrativepurposes only and form no part of the claimed design.

The ornamental design for a pen cap, as shown and described.